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From: Charles Hixson <charleshixsn@earthlink.net>
Subject: Re: Operators -> unit analysis
Date: 2000/01/05
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Matthew Heaney wrote:

> ...

> You can already do this:
>
>   Speed := Miles'(37.0) / Hours'(1.5);
>
> I always recommend type qualification for literals when units are an
> issue.
>

That handles the units problem, but the syntax is still backwards for how it needs
to be read.  I suppose there's no way out. (And I'm being picky).  But:
  Speed := Miles'(37.0) / Hours'(1.5);
is read as:
  Speed := (37.0)'Miles / (1.5)'Hours;
And even there, for a simple statement like this I would prefer:
  Speed := 37.0'Miles / 1.5'Hours;
Actually, this would probably be as near to optimal as is realizable.
But defining each unit separately has problems.  I like the general approach used
by Pat Rogers:

> I have a facility somewhat like that on the "free code page" at my web
> site:
>
> http://www.classwide.com/products/freecode.htm
>
> Look for the "dimensioned units" section (at the bottom).
>
> --
> Pat Rogers                            Training and Consulting in:
> http://www.classwide.com      Deadline Schedulability Analysis
> progers@classwide.com        Software Fault Tolerance
> (281)648-3165                       Real-Time/OO Languages
>
as it feels more "generalizeable".